WC
William Cassidy — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Suffolk-County, Massachusetts
Our Model Tree links this William Cassidy across the 1930 and 1940 US Censuses in Suffolk-County, Massachusetts (XGBoost, ~Confirmed) — first a son (b.~1930), then head of a 6-person household.
Age 10
b. ~1930
Male
Son
Born: Massachusetts
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Suffolk-County, Massachusetts |
| Surname | Cassidy |
| Given Name | William |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 10 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston |
| 1935 Residence (County) | Suffolk |
| Additional Details | |
| Highest Grade | G 4 |
| 1935 Residence | Same place |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
| Township / Ward | Boston |
| Est. Birth Year | ~1930 |
Household Members
Census records only state relationship to the household head.
Pairwise kinship is derived (~90–95% accurate), not recorded.
Step/blended families and boarders can break it.
6 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to William | Age | Birth yr |
|---|---|---|---|---|
| Nancy Cassidy | Daughter | — | 7 | ~1933 |
| Francis Cassidy | Son | — | 2 | ~1938 |
| Herbert Cassidy | Son | — | 9 | ~1931 |
| William Cassidy | Son | — | 10 | ~1930 |
| William Cassidy | Head | — | 33 | ~1907 |
| Catherine Cassidy | Spouse | — | 31 | ~1909 |
Census Appearances
1930
Suffolk, Massachusetts
Other, age
Suffolk, Massachusetts · implied b. ~1930 — 50 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Cassidy |
| Given Name | William Jr. |
| Relationship to Head | Lodger |
| Sex | M |
| Color / Race | White |
| Age | 0 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Canada-English |
| Mother's Birthplace | Ireland |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1940
Suffolk-County, Massachusetts
Son, age 10
Suffolk-County, Massachusetts · implied b. ~1930 — 6 household members
| Surname | Cassidy |
| Given Name | William |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 10 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston |
| 1935 Residence (County) | Suffolk |
| Highest Grade | G 4 |
| 1935 Residence | Same place |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
Model Tree
An inferred pedigree reconstructed from census links — up to 4 generations within the 1900–1950 window. Closer generations are built from household co-residence; deeper ones are bridged by following a relative to their own childhood census. Confidence compounds and weakens with each generation.
Our Model Tree links William Cassidy across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
William Cassidy
Son · 1940 · age 10 · b. ~1930 · Massachusetts
★ You are viewing this record
Sibling
Francis Cassidy
Sibling · 1940 · age 2
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Nancy Cassidy
Sibling · 1940 · age 7
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Herbert Cassidy
Sibling · 1940 · age 9
Source co-child of head (derived)
● Co-child · derived · ~0.88
Confirmed / household (~0.90+)
Probable / derived (~0.65–0.89)
Candidate (<0.65, unverified)
Original Census Page
1940 US Federal Census — Suffolk-County, Massachusetts
Open full size
1940 US Federal Census — Suffolk-County, Massachusetts
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01671-00500)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Helen Heider | 15 | Daughter | — | Massachusetts |
| 2 | William F. Cassidy | 33 | Head | Superintendent | Canada English |
| 3 | Catherine R. Cassidy | 31 | Wife | — | Eire |
| 4 | William Cassidy THIS PERSON | 10 | Son | — | Massachusetts |
| 5 | Herbert Cassidy | 9 | Son | — | Massachusetts |
| 6 | Nancy Cassidy | 7 | Daughter | — | Massachusetts |
| 7 | Francis Cassidy | 2 | Son | — | Massachusetts |
| 8 | Patrick Barry | 43 | Head | Laborer | Eire |
| 9 | Ellen Barry | 39 | Wife | — | Eire |
| 10 | John Barry | 9 | Son | — | Massachusetts |
| 11 | Joseph Barry | 6 | Son | — | Massachusetts |
| 12 | James Barry | 5 | Son | — | Massachusetts |
| 13 | John A. Magan | 52 | Head | Agent | Massachusetts |
| 14 | Mary R. Magan | 52 | Wife | — | Massachusetts |
| 15 | Mary L. Magan | 24 | Daughter | Clerk | Massachusetts |
| 16 | Gertrude J. Warrigan | 49 | Head | Sales-Clerk | Massachusetts |
| 17 | Joseph J. Maloney | 68 | Head | Guest Cutter | Massachusetts |
| 18 | Ellen D. Maloney | 63 | Wife | — | Massachusetts |
| 19 | Robert J. Maloney | 25 | Son | Chocolate Maker | Massachusetts |
| 20 | Enzo G. Brooker | 22 | Foster Son | Chocolate Maker | Massachusetts |
| 21 | Francis Petras | 17 | Foster Son | — | Massachusetts |
| 22 | Margaret Millen | 45 | Head | — | Canada English |
| 23 | John Millen | 15 | Son | — | Massachusetts |
| 24 | Eleanor Millen | 8 | Daughter | — | Massachusetts |
| 25 | Walter J. Markley | 47 | Head | Laborer | Massachusetts |
| 26 | Florence M. Markley | 39 | Wife | — | Massachusetts |
| 27 | Marie Markley | 12 | Daughter | — | Massachusetts |
| 28 | Florence Markley | 10 | Daughter | — | Massachusetts |
| 29 | Walter Markley | 9 | Son | — | Massachusetts |
| 30 | Margaret E. Driscoll | 55 | Sister in law | — | Massachusetts |
| 31 | John S. Wizmanel | 28 | Head | Presser | Massachusetts |
| 32 | Anna E. Wizmanel | 28 | Wife | Photographic Assistant | Massachusetts |
| 33 | Jeremiah J. Carmody | 63 | Head | Driver-Mechanic | Massachusetts |
| 34 | Alice L. Carmody | 62 | Wife | — | Massachusetts |
| 35 | Francis X. Carmody | 23 | Son | Maintenance Man | Massachusetts |
| 36 | William E. Carmody | 19 | Son | Counter-Clerk | Massachusetts |
| 37 | Martin Walsh | 52 | Head | Electrician Helper | Eire |
| 38 | Barbara Walsh | 50 | Wife | — | Eire |
| 39 | Marion Walsh | 23 | Daughter | — | Massachusetts |
| 40 | Kathleen Walsh | 10 | Daughter | — | Massachusetts |
About This Record & Model Tree
This record was independently indexed by YourRoots from the 1940 United States Federal Census (NARA). Our Model Tree links this person across census decades using XGBoost-based record linkage, with per-link confidence scores. Household corroboration strengthens the signal when co-residents appear on the same census pages in multiple years.
Source: National Archives and Records Administration (NARA)